Structures which are occasionally subject to sustained high winds, such as structures located in regions subject to hurricanes, preferably have substantial connections between components of the structure to increase the strength of the structure and prevent damage in high winds. Building codes in these regions require that there be additional connections between trusses. in the roof, joists in the floor and the walls to anchor the roof and floor. For instance, it may be required to anchor each end of a truss or floor joist to the adjacent wall with a hold down strap.
It is well known to provide flexible metal straps for the purpose of connecting the roof truss (or floor joist) to a stud in an adjacent wall. An example of such a strap is shown in U.S. Pat. No. 3,861,094 (Jureit et al.). The Jureit et al. strap is an elongate piece of sheet metal formed at either end with teeth projecting outwardly from the sheet metal. Small, spaced apart sections are erupted from the sheet metal as by punching to define the teeth. The ends of the strap are driven into the truss and into a stud in the wall, respectively, to secure one to the other.
Toothed hold down straps can be hammered into the truss (or joist) and adjacent wall by laborers at the construction site. However, this is a time consuming process and often requires the laborers to get into precarious positions high up on the structure near the edge of the roof to secure the hold down straps to the wall. Moreover, the hold down straps must be stored by the laborers and then located when needed for securing the truss. It is known to secure one end of a toothed strap to the truss at a plant where the truss is assembled so that the strap is integrated with the truss prior to erecting the truss on the wall of the structure. The end of the toothed hold down strap can be pressed into the truss by the same press used to drive other nailing plates into adjoining wooden elements forming the truss. At the construction site, the laborer need only secure the other end of the strap to an adjacent stud.
The sheet metal must be sufficiently strong so that the teeth formed can be driven into the wooden elements of the truss or joist and the wall. There must be enough thickness in the sheet material so that teeth punched from the sheet material will not simply bend over rather than penetrating the wood of the truss components when pressed against them. Sheet material having this thickness (e.g., 22 gauge sheet metal) is thicker than needed to adequately secure the truss to the wall. Thus, the cost of the straps is high because the sheet metal must be quite heavy so that teeth formed are of sufficient strength. Further, the formation of the teeth in the hold down straps is an additional step in the construction process, whether the hold down straps are secured to the truss at the construction site or at the assembly plant. The tooth formation step, which is in addition to the step of stamping out the hold down straps from a web of sheet metal, also adds to the cost of the truss. Thus, it would be desirable to have a truss assembly with an integral hold down strap that is easily fastened to a wall and is inexpensive to manufacture.